With more greenhouse gases trapping heat, average annual global temperatures are rising. This is known as global warming.
While temperatures have risen since the end of the Pleistocene, 10,000 years ago, this rate of increase has been more rapid in the past century, and has risen even faster since 1990. The 10 warmest years in the 134-year record have all occurred in the 21st century. The warmest year on record was 2016, with 2015 and 2014 being the second and third warmest.
Greenhouse gases trap heat in the atmosphere; burning fossil fuels and other human activities release greenhouse gases into the atmosphere; greenhouse gas levels in the atmosphere are increasing; and global temperatures are increasing.
Average global temperature has been rising since the end of the ice ages but the rate of its rise has increased in recent decades.
Changes due to increasing temperatures are seen around the globe but are most dramatic in the polar regions.